//
/***********************************************************
             File name:      main.c
             Author:         Bitat (陆叁柒)
             Email :         Bitat@qq.com
             Gitee :         https://gitee.com/bitat
             CSDN  :         https://blog.csdn.net/bitat 
             History:        2023/3/22
************************************************************/
    
#include <stdio.h>

//球的体积
int main()
{
    double pi = 3.1415927;
    double r = 0;
    scanf("%lf",&r);
    printf("%.3lf\n",(4*pi*r*r*r)/3);//将分子放在一起
    //printf("%.3lf\n",(4/3)*pi*r*r*r);
    
    return 0;
}
